Transcript physical evolution of humans

Introductory Question - Did early
man live at the same time as
dinosaurs?
• The answer to that one is simple. Nah! No way. Not a chance.
• Nobody knows for sure why dinosaurs disappeared, but they do
know that dinosaurs died out about 65 million years ago. The
first hominids (human-like primates) did not appear until 3.6
million years ago.
• Even if scientists are off a few million years or so, early man
simply did not live during the same period in history as
dinosaurs.
• This is not to say that early man had it easy. They did have to
face sabre-toothed tigers, cave lions, and woolly mammoths! But,
they did not have to fight dinosaurs!
PHYSICAL
EVOLUTION OF
HUMANS
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Evolution traces human development
through several stages or species from the
first humanlike beings to modern humans.
Do not know exactly when the evolution of
humans and apes diverged
HOMINIDS
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Humanlike creatures began to
appear over four million years
ago. Members of the human
family tree.
Distinguished from apes most
notably
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By their bipedalism (ability to
walk on two feet)
Larger brain size
Bipedalism
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Positives of
Bipedalism
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Walking on two
feet left hands free
to perform many
tasks, including
young over long
distances and
making tools and
weapons.
What prompted first hominids to
begin walking on two feet?
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Can only speculate
On theory, still unproven, is that climate
change transformed eastern and southern
Africa forests into dry, open grasslands.
This terrain might have favoured the
survival of apes that could walk upright.
(have to travel long distances)
THE STONE AGE
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Called the Stone Age because
most of the artifacts found from
this time are made of stone.
Stone Age divides into 3 Ages.
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Paleolithic or Old Stone Age (2
million BCE – 10, 000 BCE)
Mesolithic or Middle Stone Age (10,
000 BCE – 8,000 BCE)
Neolithic or New Stone Age (8,000
BCE – 5,000 BCE)
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Humans who lived in
the Stone Age are
generally classified into a
group called HOMO.
HOMO divided into two
overlapping species:
HOMO ERECTUS
AND HOMO
SAPIENS
HOMO HABILIS
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“Handy Man” flourished in
Africa about 2.5M years ago.
First to develop and use stone
tools (proof of their ingenuity
and creative ability)
Brain size and presence of
humanlike teeth suggest
Homo habilis might have
been our human ancestor.
HOMO ERECTUS
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First appeared about 2 million years ago.
Name refers to the fact that they could walk
completely upright, like modern humans
Skulled shaped different from us. Braincase was long
and broad at the base. Had massive eyebrow ridges and
high bony crests at the neckline.
HOMO ERECTUS
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Probably survived by
hunting wild animals and
gathering plants for food.
With their increasing skills,
they made tools of stone,
bone and wood.
First species to use fire and
first to migrate into Europe
and Asia from Africa
HOMO SAPIENS
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“MAN WHO THINKS”
Formulated the spoken
language and developed more
sophisticated tools.
Oldest remains found in Hungary
others from England, Germany
Skull shape is different from
Erectus although the size is
similar.
NEANDERTHALS
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Located in Europe about 230 000
years ago – disappeared approx.
30, 000 years ago
From central Europe
Neanderthals traveled east into
central Asia, even migrating into
the Middle East
Questions remains on whether
Neanderthals are our direct
ancestors or whether they were a
separate species, driven to
extinction by modern humans.
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Neanderthals were
formidable hunters and
gatherers.
Hunted small rhinoceroses
and other large animals
such as elk, bison and even
mammoths. Gathered
edible plants, shellfish, and
small reptiles.
Why did the Neanderthals
disappear?
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Modern humans wiped them out? (brought
in diseases)
Died out because they couldn’t compete
with modern humans?
HOMO SAPIENS SAPIENS
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About 40,000 years ago, modern humans moved
into Europe armed with skills to make clothing,
better shelters and more efficient hearths.
Named Cro-Magnon people after the French rockshelter where 3 modern skeletons were discovered in
1868
Cro-Magnons were Homo Sapiens who evolved in
Africa and slowly pushed their way into Europe.
Developed the ability to endure colder climates,
even those as cold as Iceland and Greenland.
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Cro-Magnon people were about as tall as modern northwestern
Europeans.
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Men 180 cm Tall.
Women 180 cm tall.
Many of the same features as modern northwestern Europeans.
High foreheads, curving noses, large jaws and small teeth and
small teeth.
Eventually their successors moved into Asia.
About 30, 000 years ago, they crossed the Bering Strait after
the retreat of the ice and entered the Americas, others
Australia.
Use your notes and textbook to
answer the following questions:
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6.
On what continent have the fossils of the earliest
human ancestors been found? (p. 8)
Who is Charles Darwin? (p. 9)
Explain the process of natural selection. (p. 10-11)
Why was Darwin’s theory considered revolutionary?
(p. 10-11)
Who is Lucy and why is she important? (p.14)
Do you think human evolution continues or have we
as a species stopped evolving? Explain your answer.
1. On what continent have the fossils
of the earliest human ancestors
been found?
Africa
2. Who is Charles Darwin?
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English biologist
Known for creating in detail the theory of
evolution
3. Explain the process of natural
selection.
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The strongest of a species survives while the
weaker dies
Only those who can adapt to their changing life
and surroundings will survive
Survival of the fittest
4. Why was Darwin’s theory
considered revolutionary?
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Darwin’s theory went against the popular believe
of the time, creationism. Creationism is the
belief that God created man and the world.
5. Who is Lucy and why is she
important?
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In 1974, a female hominid was found in Africa.
She was named Lucy after the Beatles song
“Lucy in the Sky with Diamonds”
Lucy was 3.18 million years old; the oldest fossil
found.
This discovery suggests that humans originated
in Africa.
6. Do you think human evolution
continues or have we as a species
stopped evolving? Explain your answer.
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Humans have evolved for thousands of years,
why would we stop now?
Our environment may change (perhaps caused
by global warming), we will have to adapt to
survive in our new environment
Remember, changes are subtle and take many
generations to take place
Quiz
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10.
What are primary documents?
Give one example of a primary document.
What are secondary documents?
Give one example of a secondary document.
Define the term “history”.
What is a creation myth?
What is bi-pedalism?
What is an advantage of bi-pedalism?
How did the Stone Age get its name?
On which continent did early man originate?